This study demonstrated a controllable release properties and synergistic antibacterial actions between orange essential oil (OEO) and silver nanoparticles (AgNPs) incorporated onto cellulose (CL) nanofibers. The preparation of AgNPs attached on CL nanofibers was conducted through multiple processes including the deacetylation process to transform cellulose acetate (CA) nanofibers to CL nanofibers, the in situ synthesis of AgNPs, and the coating of as-prepared silver composite CL nanofibers using OEO solutions with two different concentrations. The success of immobilization of AgNPs onto the surface of CL nanofibers and the incorporation of OEO into the polymer matrix was confirmed by SEM-EDS, TEM, XRD, and FT-IR characterizations. The tensile strength, elongation at break, and Young’s modulus of the nanofibers after each step of treatment were recorded and compared to pristine CA nanofibers. The high antibacterial activities of AgNPs and OEO were assessed against Gram-positive B. subtilis and Gram-negative E. coli microorganisms. The combined effects of two antimicrobials, AgNPs and OEO, were distinctively recognized against E. coli.

We report on numerical investigation of the electrocaloric effect, an important physical phenomenon in compositionally graded ferroelectric (CGFE) nanowires made of Pb(1−x)SrxTiO3 whose material compositions spatially vary along the longitudinal direction of nanowires. In this study, all numerical evidences are demonstrated through the phase field model based on the Ginzburg–Landau theory. Here, the change of polarization with temperature can be tailored by controlling the gradient of material compositions in CGFE nanowires. The isothermal entropy and adiabatic temperature changes are enhanced with an increasing compositional gradient in CGFE nanowires. The electrocaloric effect is found to have high magnitude near room temperature in CGFE nanowires of PbTiO3 (top surface)/SrTiO3 (bottom surface), which is much larger than that in homogeneous ferroelectric nanowire with the same average material composition. In addition, the high electrocaloric effect in CGFE nanowires of PbTiO3/SrTiO3 is achieved in a wide range near room temperature. We also discuss the potential of CGFE nanowires for electrocaloric cooling applications, and more importantly, this work, in essence, opens a new route to enhance the electrocaloric properties of ferroelectric nanowires near room temperature by controlling the gradient of material compositions.

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This study demonstrates a controllable release properties and synergistic antibacterial actions between orange essential oil and silver nanoparticles incorporated onto cellulose nanofibers. The preparation of silver nanoparticles (AgNPs) attached on cellulose nanofibers was conducted through multiple processes including the deacetylation process to transform cellulose acetate nanofibers to cellulose nanofibers, the in-situ synthesis of AgNPs, and the coating of as-prepared silver composite cellulose nanofibers using orange essential oil (OEO) solutions with two different concentrations. The success of immobilization of AgNPs onto the surface of cellulose nanofibers and the incorporation of OEO into the polymer matrix was confirmed by SEM-EDS, TEM, XRD, and FTIR characterizations. The tensile strength, elongation at break, and Young’s modulus of the nanofibers after each step of treatment were recorded and compared to pristine CA nanofibers. The high antibacterial activities of AgNPs and OEO were assessed against gram-positive B. subtilis and gram-negative E. coli microorganisms. The combination effects of two antimicrobials, AgNPs and OEO, were distinctively recognized against B. subtilis.